"The original idea was to go to a couple of producers whose work I loved, to see who I got on with best," McCartney, 71, said in a statement. "But it turned out I got on with all of them. We made something really different with each producer, so I couldn't choose and ended up working with all four. We just had a good time in different ways."
Martin, the son of Beatles producer George Martin, produced half of the album's dozen tracks, while Ronson, Epworth and Johns produced two each.
That's led to a varied sound over the course of "New" that the ex-Beatle says has led to some surprises to those for whom he's played the album.
"It's funny, when I play people the album they're surprised it's me," McCartney said. "A lot of the tracks are quite varied and not necessarily in a style you'd recognize as mine.
"I didn't want it to all sound the same. I really enjoyed making this album. It's always great to get a chance to get into the studio with a bunch of new songs, and I was lucky to work with some very cool producers. We had a lot of fun."
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